Efficient synthesis of isoxazolidine-substituted bisphosphonates by 1,3-dipolar cycloaddition reactions

Organocatalytic Enantioselective Epoxidation of Some Aryl-Substituted Vinylidenebisphosphonate Esters: On the Way to Chiral Anti-Osteoporosis Drugs

“…This situation reflects the problems of dealing synthetically with molecules having a bisphosphonate group which induces (i) a strong electrophilicity on the central C atom and eventually on adjacent moieties; (ii) a significant steric hindrance leading in many cases to limited accessibility and poor reactivity; and (iii) the capacity of strongly binding metal ions, thereby inactivating catalysts in transition metal-catalyzed reactions. A useful synthetic approach allowing the formation of a broad range of BPs is based on vinylidenebisphosphonate precursors (VBPs) as starting materials [15][16][17][18]. The application of a series of enantioselective catalytic reactions based on the use of a variety of nucleophilic reagents towards these precursors opens the way to the possibility of obtaining a wide range of structurally complex BPs, and in principle the opportunity to verify the different behaviors of the synthesized enantiomers.…”

“…A useful synthetic approach allowing the formation of a broad range of BPs is based on vinylidenebisphosphonate precursors (VBPs) as starting materials [15][16][17][18]. The application of a series of enantioselective catalytic reactions based on the use of a variety of nucleophilic reagents towards these precursors opens the way to the possibility of obtaining a wide range of structurally complex BPs, and in principle the opportunity to verify the different behaviors of the synthesized enantiomers.…”

Modified N,O-Nucleosides: Design, Synthesis, and Anti-tumour Activity

“…[16] With the set of nitrones 3f-j in hand, we initially synthesized compounds 5f-h by 1,3-dipolar cycloaddition with vinylthymine as nucleobase 4, according to the general procedure described in the Experimental section. Then, the N,O-nucleoside derivatives 5f-h were evaluated by in vitro assays for their antiproliferative activity against SKOV3 and SW480 cell lines.…”

“…[12,16,[21][22][23][24][25][26][27] The full characterization of compounds 3f-j can be found in references [16] and [24][25][26], and for 5a-e in reference [13].…”

Pyrrolidine‐Containing Bisphosphonates as Potential Anti‐Resorption Bone Drugs

“…Through this method, BPs with heterocycles, [14] steroidc onjugates, [15] or other functional groups at the b position, such as thiols, [16] have been reported in the literature. [17,18] groups.F or example, VBP acts as an efficient dienophile [19] for cycloaddition reactions with dienes [20] and nitrones [21] to provide cyclic BPs and isoxazolidine-substituted BPs, respectively. [17,18] groups.F or example, VBP acts as an efficient dienophile [19] for cycloaddition reactions with dienes [20] and nitrones [21] to provide cyclic BPs and isoxazolidine-substituted BPs, respectively.…”